Exhaust silencer



Oct. 22, 1940. E. J. PALMER 2,218,959

EXHAUST SILENCER Filed Feb. 29, 1940 3 Sheets-Sheet l 3 In uentor flhesf J a/mer By MM M A .fomeys Oct. 22, 1940. E. J. PALMER EXHAUST SILENCER Filed Feb. 29, 1940 3 Sheets-Sheet 2 W W 1 MUN HIHWUIHMI Hill] Inventor By 2mm.

Aiiomeys Oct. 22, 1940. E J PALMER 2,218,959

EXHAUST SILENCER Filed Feb. 29, 1940 3 Sheets-Sheet 3 Inventor A iiorneys Patented Oct. 22, 1940 PATENT OFFICE EXHAUST SILENCER Ernest J. Palmer, Rutherford, N. J., assignor of one-half to Harlan W. Sarvis, Bayonne, N. J.

Application February 29, 1940, Serial No. 321,579

2 Claims.

This invention relates to an exhaust muilier or silencer especially adapted for any type of internal combustion engine or a steam locomotive, and has for the primary object the provision of a device of this character which will reduce exhaust noise to a minimum and reduce back pressure on the engine or locomotive to a minimum to permit either the engine or locomotive to operate efllciently and to develop a maximum amount ofhorse power.

With these and other objects in view, the invention consists in certain novel features of construction, combination an arrangement of parts to be hereinafter more fully described and claimed.

For a complete understanding of my invention, reference is to be had to the following description and accompanying drawings, in which Figure 1 is a fragmentary vertical sectional view showing a portion of a locomotive equipped with a silencer constructed in accordance with my invention.

Figure 2, is a side elevation illustrating an inner shell and pressure breakers carried thereby.

Figure 3 is a side elevation illustrating an intermediate shell.

Figure 4 is an end view of the intermediate shell.

Figure 5 is a side elevation, partly in section, of the outer shell.

Figure 6 is an end view of the inner shell.

Figure 7 is a side elevation, partly in section, illustrating a modification of the present invention and of the character especially adapted for internal combustion engines.

Figure 8 is a vertical sectional view illustrating the modified form of the invention.

Figure 9 is a transverse sectional view taken on the line 99 of Figure 8.

Referring in detail to the drawings, the numeral 5 indicates a fragmentary portion of a locomotive having located in the smoke box 6 thereof a silencer or muiller I constructed in accordance with the present invention.

The muffler I includes an inner shell 8, an intermediate shell 3 and an outer shell II). The inner shell 8 includes an elongated tubular body II having integral with one end an attaching flange I2 adapted to be bolted to a correspondingly shaped flange I3 of the exhaust pipe I4 of the locomotive. The elongated tubular body II has integral with the exterior thereof exhaust pressure breakers I5, I6 and I1. Also integral with the elongated tubular body I I adjacent the flange I2 is an end cap I8, a portion of which is externally screw threaded. The breakers IS, IS and I! are of annular formation and are spaced from each other. The breaker I5 has formed therein a series of peripheral grooves I9 having a spiral pitch thereto. The breaker I6 is also provided with peripheral grooves having a spiral pitch thereto and extending in an opposite direction to the grooves I9. The breaker I! is provided with spiral grooves 2I also provided with a spiral pitch thereto corresponding to the pitch of the grooves I9 of the breaker I5.

The intermediate shell 9 is placed over the inner shell with contact with the peripheries of thebreakers I5, I5 and II, the grooves of said breakers forming a series of exhaust passages which will impart to the fiow of exhaust a whirling mot-ion first in one direction and then in another direction. The breaker H has on the pe riphery thereof screw threads to match internal screw threads 22 of the intermediate shell whereby the latter is secured in place on the inner shell. One end of the intermediate shell is closed and rounded and spaced from the discharge end of the inner shell.

Formed on the exterior of the intermediate shell are breakers 23 and 24 provided with peripheral grooves 25. The peripheral grooves 25 of the breaker 24 have a spiral pitch thereto while the grooves 25 of the breaker 23 are disposed straight.

The outer shell I has one end internally screw threaded to thread onto the cap I8 while the opposite end is rounded and is provided with a pipe-like portion 26 opening to the atmosphere or to the interior of the firebox of the locomotive directly under the smoke stack.

The breakers 23 and 24 engage the interior walls of the outer shell I and the grooves 25 thereof provide a series of exhaust passages.

Referring to Figure 1 it will be seen that the exhaust enters the lower end of the inner shell 8 and discharges therefrom at the upper end against the rounded end of the inner shell and then passes downwardly in the space defined between the inner and intermediate shells passing through the various grooves of the breakers I5, I6 and I! where the exhaust is compelled to travel with swirling motion first in one direction and then in an opposite direction. The exhaust leaves the lower end of the intermediate shell into the cap I8 where it is reversed upward-1y to pass between the intermediate shell and the outer shell being compelled to pass through the grooves of the breakers 24 and 23 before reaching the exhaust pipe 26. By the time the exhaust reaches the exhaust pipe 26 its force has been reduced to a minimum so that on reaching the atmosphere the sound of the exhaust will be reduced to a minimum. The exhaust traveling through the inner, intermediate and outer shells as specified will 'be allowed to gradually expand and thereby reduce its force.

The silencer besides being connected to the exhaust pipe of the locomotive may further be connected to the walls of the smoke box by a series of braces 21. This type of silencer or muflier may also be successfully employed upon heavy duty internal combustion engines. Further, it will be noted that the mufiler or silencer of this construction can be readily taken apart for cleaning and repairing when necessary.

Referring to my modified form of invention as shown in Figures 7 to 9, inclusive, the silencer is indicated generally by the character 28 and consists of an outer shell 29, an intermediate shell 30 and an inner shell 3|. These shells are preferably constructed of light gauge metal and thereby permits this type or form of silencer to be efliciently used in connection with internal combustion engines frequently employed in automobiles, trucks or the like, the silencer being mounted on the vehicle by a series of sprockets 32 welded onto the outer shell as well as to the inner shell or that portion which extends outwardly of the outer shell. In this form of the invention the inner shell 3| is in the form of a pipe, one end of which may be suitably connected to the exhaust pipe of an internal combustion engine and the other end terminates within the intermediate shell spaced from the dome-shaped closed end 33 thereof. Exhaust breakers 34, 35 and 36 are formed on the inner shell and the peripheries thereof are in contact with the inner walls of the intermediate shell. The breakers 34, 35 and 36 are grooved in accordance with the grooving of the breakers I5, l6 and I! to provide a series of exhaust passages through which the exhaust must travel when passing through the intermediate shell. A dome-shaped cap 31 is integral with the inner shell and has a suitable joint with the outer shell 28. -The intermediate shell has breakers 38 and formed thereon which contact the interior walls of the outer shell and are grooved in accordance with the breakers 23 and 24. The joint between the cap 31 and the outer shall may be in the form of a well while the other end of the outer shell has integral therewith an exhaust pipe 39 opening to the atmosphere.

It is to be understood that prior to welding of the cap 31 onto the outer shell, the inner and intermediate shells are assembled in relation to each other and within the outer shell. This type of silencer will have the efliciency of the type of silencer described in connection with the locomotive and for heavy internal combustion engines but may be manufactured at a lower cost.

The flow of exhaust through the silencer as shown in Figures 7 to 9 is in accordance with that described in connection with the silencer shown in Figure 1 so that the exhaust on reaching the atmosphere will be substantially noiseless. Also this type of silencer will reduce back pressure on the engine to a minimum.

It is believed that the foregoing description, when taken in connection with the drawings will fully set forth the construction and advantages of this invention to those skilled in the art to which such a device relates, so that further detailed description will not be required.

Having thus described the invention, what I claim is:

1. In a device of the class described, inner, intermediate and outer shells having communication with each other at certain ends thereof and the outer shell opening to the atmosphere at one end thereof, means for connecting one end of the inner shell to an exhaust pipe, said shells coacting with each other in forming exhaust passages therebetween in which the exhaust must first travel in one direction endwise of said shells and then in an opposite direction endwise of said shells and then in a reverse direction endwise of said shells before reaching the atmosphere, exhaust breakers arranged in the exhaust passages between the inner and intermediate shells and the intermediate shell and the outer shell and of annular formation having peripheral grooves to form a series of restricted exhaust passages, the grooves of certain of said breakers having spiral pitches thereto and certain breakers being so arranged that the pitches of the grooves thereof'extend in an opposite direction to the pitches of the grooves of adjacent breakers.

2. In a device of the class described, inner, intermediate and outer shells of tubular formation having communication with each other at certain ends and the outer shell having one end closed and provided with an opening communicating with the atmosphere, means for connecting one end of the inner shell to an exhaust pipe,

a. cap formed on the inner shell, means for connecting the cap to the outer shell, annular exhaust breakers formed on the inner and intermediate shells for the support of said shells in relation to each other and the outer shell and provided with peripheral exhaust grooves, one of the breakers of the inner shell having screw threads, said inner shell having screw threads to thread onto the latter-named breaker.

ERNEST J. PALMER. 

